1. Field of the Invention
The present invention relates to a new and improved multi-purpose hand tool with multiple interchangeable utility heads. More particularly, the present invention relates to a device which enables selective tool configuration by providing a durable, versatile, and economically produced professional hand tool that is compact and provides maximum safety features for high demand usage.
2. Description of the Related Art
Today""s growing housing market and service and repair industry is placing a great demand upon construction and repair professionals for quick and efficient performance which often require long hours in difficult physical conditions. The rigors of various professions are often exacerbated by the weight and bulk of hand tools which must be necessarily carried upon persons when climbing ladders, scaffolds and in tight spaces. This places an increased burden upon physical stamina and endurance, decreases maneuverability and balance, and sometimes compromises safety on the job. In such settings, multi-purpose hand tools represent an effective means of reducing load weight, while providing the user with an effective means of having selective tool configurations readily available.
Such a multi-purpose hand tool may be readily adapted to circumstances which require specialty tools such as auto body repair, or other metal-working uses such as sheet metal fabrication and installation, where multi-purpose, interchangeable utility tools might speed the process and reduce space requirements for storage and quick access to tools.
The necessity and usefulness of hand tools with interchangeable heads are well known. Examples of different types and kinds of devices with interchangeable heads are disclosed in U.S. Pat. Nos. 4,183,385, 4,399,978, 4,440,206, 5,216,939, 5,526,719 and 5,255,575.
In general, the structure and function of most of these hand tools with interchangeable heads involve a handle permanently attached to a base frame. The base frame then provides for a means to detachably mount a utility head and secure such head in a manner which would provide safe usage of the tool. A limited number of such hand tools provide for a combined head and base frame unit which then detachably mounts to a handle as a single unit.
Hand tools with detachably mounted utility heads are known in the prior art. Such a device is described in U.S. Pat. No. 4,183,385. The device comprises a base frame/claw combination permanently fixed to a handle. The base frame has an end with a circular bore that accepts interchangeable heads which are secured by means of a yoke and a locking pin assembly.
The locking pin and associated pull tab are located in close proximity to the detachably mounted utility head. The major portion of those utility heads are meant to be used in a striking or hammering situation. During usage of an implement in these situations, there will inevitably be ill placed strikes. In the process of those missed impacts, the locking pin and pull tab are positioned in such a manner as to be easily damaged by other objects including nail heads and would render the instrument useless as a multi-use tool.
In addition, the close machining tolerances for the matching transverse bore holes located in the base frame and the longitudinal shaft portion of the interchangeable head would be extremely expensive to manufacturing. Even a small deviation may cause damage to the locking pin during striking or hammering which could damage the locking pin to the point that it could not be removed, or cause the formation of cracks in the locking pin which could make the device dangerous to the user or others nearby.
Furthermore, there is no mechanism provided which would provide for an interchangeable handle should the handle become worn or should the particular usage of the device dictate a handle made from a different material.
Therefore, it would be highly desirable to have a new and improved device and method for making same for a multi-purpose hand tool with multiple interchangeable utility heads which would provide for a safe and effective mechanism for attachment of the interchangeable utility heads so they would not be damaged by missed hits or less than perfect machine tolerances, which would supply a means that would allow interchangeable handles and would be economically manufactured.
The device described in U.S. Pat. No. 4,399,978 addresses the problem of providing a mechanism for an interchangeable handle but does not provide for interchangeable utility heads. This device teaches a tool with a combined base frame and utility head combination which has variable inclination relative to its handle. The base and utility head combination are attached to a handle by means of a latch rod.
Therefore, it would be highly desirable to have a new and improved device and method for making same for a multi-purpose hand tool with multiple interchangeable utility heads which would provide a mechanism to safely secure the base frame to a replaceable handle and at the same time provide a mechanism to safely secure interchangeable utility heads to the base frame as well.
U.S. Pat. No. 4,440,206 describes a device that addresses the problem of a detachable handle. The device provides for a number of combined base frame/utility heads. However, the combination of the base frame and the utility heads restrict the flexibility of the device and does not appreciably reduce the total bulk of the combined tools for easy storage or transportation.
Additionally, the position of the threads and collar place it in an area vulnerable to missed hits while in use as a hammering tool. Missed hits resulting in damage to the threads or collar may prevent removal of the handle or the combined base frame/utility heads.
Therefore, it would be highly desirable to have a new and improved device and method for making same for a multi-purpose hand tool with multiple interchangeable utility heads which would provide for maximum versatility with interchangeable utility heads and have a replaceable handle that would not be subject to damage from missed hits when used as a hammering tool and would be compact in size and easy to transport and store.
U.S. Pat. No. 5,216,939 provides for a hammering hand tool with a single interchangeable utility head which includes variable weights inserted into the interior housing of the base frame. The single interchangeable head again does not provide for maximum versatility of the tool.
In addition, the device does not provide for a mechanism for attachment to a replaceable handle.
Therefore, it would be highly desirable to have a new and improved device and method for making same for a multi-purpose hand tool with multiple interchangeable utility heads and a replaceable handle which would be compact, solidly constructed and easy to transport and carry.
A device for interchangeable heads is described in U.S. Pat. No. 5,255,575. The interchangeable heads are attached to the base frame by means of a wedge shaped portion which is inserted into a corresponding slot in the base frame. The tips are held in place presumably by a friction fit which may become compromised with repeated hammer hits that force the wedge shaped portion of the tip to distort or damage the corresponding slot in the base frame. If the friction fit is compromised, the tool would become dangerous to the user or others in the vicinity during use.
In addition, there is no means provided for attachment of a replaceable handle. Therefore, it would be highly desirable to have a new and improved device and method for making same for a multi-purpose hand tool with multiple interchangeable utility heads and a replaceable handle which would provide for attachment mechanisms which would remain safe to use even after multiple striking hits with the tool and which provides the user with an attachment for an interchangeable handle.
Finally, U.S. Pat. No. 5,526,710 describes a device that has a hollow base frame attached to a handle. The hollow base frame supports two hollow frame holders at opposite ends of the base frame to which various interchangeable heads may be attached. The device does not provide for any attachment mechanism between the hollow base frame and the handle and no safety mechanism to insure that the base frame does not detach from the handle when in use.
In addition, the complexity of the device necessitates close tolerances in machining and high maintenance costs for replacement of the numerous parts which would make the device relatively expensive to manufacture and maintain. Furthermore, the entire base frame and portions of the detachable heads are hollow. The effective usage of a hammering tool depends largely upon the weight of the hammering end of a hand tool. The correct balance of such a tool is essential for an ergonomically efficient tool.
Therefore, it would be highly desirable to have a new and improved device and method for making same for a multi-purpose hand tool with multiple interchangeable utility heads which would provide an attachment means between the base frame portion and the handle with safety considerations built in that would be relatively inexpensive to manufacture, maintain, and with a properly weighted hammering portion which would be ergonomically efficient.
Therefore, the principal object of the present invention is to provide a new and improved device and method for making same, for a multi-purpose hand tool with multiple interchangeable utility heads. This multi-purpose tool would allow for two utility head inserts for maximum versatility for attachment of the multiple interchangeable utility heads attached by means of a mechanism designed not to be adversely affected by missed hits or repeated hammer strikes.
It is a further object of the present invention to provide such a multi-purpose tool with built in safety features. Among the utility heads for this novel invention are chisels, scrappers and other tools which would normally be hand held. The use of these utility heads would provide expanded uses while preventing potential injury to the user from missed strikes to a hand held tool.
It is a further object of the present invention to provide such a new and improved device and method for making same, multi-purpose hand tool with multiple interchangeable utility heads that would be relatively inexpensive to manufacture and maintain.
It is yet a further object of the present invention to provide such a new and improved device and method for making same, for multi-purpose hand tool with multiple interchangeable utility heads, which would also be less bulky, versatile, easily transported and stored in a compact form when not in use.
It is yet a further object of the present invention to provide such a new and improved device and method for making same, for multi-purpose hand tool with multiple interchangeable utility heads, which when in use would retain its structural and design integrity and be operationally safe and simple during usage.
It is yet a further object of the present invention to provide such a new and improved device and method for making same, for multi-purpose hand tool with multiple interchangeable utility heads, which would provide for a replaceable handle.
It is finally a further object of the present invention to provide such a new and improved device and method for making same, for a multi-purpose hand tool with multiple interchangeable utility heads which would be properly weighted for efficient ergonomic use when used as a striking or hammering tool.
Briefly, the above and further objects of the present invention are realized by providing a new and improved multi-purpose hand tool with multiple interchangeable utility heads. This multi-purpose hand tool with multiple interchangeable utility heads would have a utility head block with two utility head block accepting portions providing for maximum versatility and result in a compact, less bulky tool for convenient transportation and storage. The utility head block is constructed of appropriate materials and is solid to better absorb force upon impact and provide for proper weighting of the tool when used as a hammering or striking tool. The attachment mechanisms are designed to maintain integrity and therefore safety, even after consecutive, frequent usage. Another safety feature is the use of utility heads designed to take the place of hand held tools, thus reducing the potential for injury to the user from missed strikes to the hand held tools. The hammer head block is also designed to safely accommodate different hammer handles for various usage demands or if handles become damaged, thus extending the usable life of the tool. More particularly, the present invention relates to a device which enables a user to selectively change the configuration of the tool that he is using so as to adapt the tool to various demands of an application by providing interchangeable multiple heads and handles which quickly and safely attach to a single head block. This makes the overall size of the tool much better suited than comparable conventional tools that it would replace. The interchangeable utility heads would be inserted into the head block by means of a guide shafts and held in place by a combination of a friction fit and ball/spring assembly. The handles would be held in place with the aid of wedges and the insertion of a shaft into a bore and tube assembly and in combination with an interchangeable handle, insures that the useful life of the tool will be lengthened. The nature of the attachment configuration does not require extremely high tolerance manufacturing or a large number of parts and so the production of the device would be relatively economical, by most current and future manufacturing techniques, and the simplicity of design would mean low, if any, maintenance costs.